Abstract:Qiaogou geothermal field is located in western Qiaogou village in Culai town of Tai'an city. It was discovered in the early 1970s. It is a banded thermal reservoir type low temperature geothermal resource. By studying and analyzing the existing drilling and geothermal geological data of Qiaogou geothermal field, combining with geothermal geological survey, geothermal field survey and hydrogeochemistry, major elements, trace elements, radioactive elements and isotopic composition characteristics of geothermal water in Qiaogou geothermal field have been stuied, and the source, age and origin of geothermal water have been summarized, the concept model of Taishan rock group heat reservoir—Quaternary clayey sand and Cambrian limestone cap rock—deep circulation convection channel of fault structure and heat source of earth heat flow have been established. In Qiaogou geothermal field, Na+ and Ca2+ are main cations, SO2 4and Cl are main anions, and hydrochemical type is SO4·Cl-Na·Ca. Geothermal water is fluorine water and metasilicic acid water, which has special medical effect on skin diseases and arthritis. The geothermal water mainly comes from atmospheric precipitation and is mainly recharged from "sub modern to before 1952" due to the influence of continental leaching water evolution. The age of formation ranges from 20.41 to 30.21 years. The K-Mg temperature scale and the SiO2 temperature scale are calculated. It is speculated that the temperature of deep thermal reservoir in Qiaogou geothermal field can still rise. The origin of geothermal fluid is related to sustainable development of geothermal resources utilization. This study will provide data support for the development and utilization of geothermal resources in Qiaogou geothermal field.
